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Comment: Why is encryption not standard? (Score 1) 90

by Thagg (#48467113) Attached to: New Snowden Docs Show GCHQ Paid Telcos For Cable Taps

It's astonishing that all communication is not encrypted. If you are sharing information over a common carrier, you should expect that somebody is going to be grabbing and examining the bytes.

So, somehow, it is just not the norm to encrypt communication. One reason might be that during the eighties and nineties as the internet was going wide, ITAR and patents on systems like RSA made people and companies nervous and unwilling to go there; that was definitely a missed opportunity.

Perhaps another problem is that there's no money to be made in encryption; and there are real (small, but real) costs in establishing it.

Still, though...

Why is there no encrypted "WhatsApp"? It would not be hard, it would be trivial to deliver through Google Play, and there would be a immediate market. If the connections were truly peer-to-peer, the infrastructure to support it would be almost zero.

How has the world convinced people not to encrypt all communication?

Comment: Re:two bounces (Score 1) 223

by Thagg (#48386331) Attached to: Comet Probe Philae To Deploy Drill As Battery Life Wanes

1) There is/was a significant risk that drilling would push Philae off the comet again. Still, it's a risk worth taking; without the solar recharging ESA has only until Saturday before the batteries run out.
2) The challenge is that either the lander is on its side, so the solar panels can't see the sun; or that the lander is up against a wall blocking the sun most of the time. They are considering possible ways of reorienting Philae; but it doesn't seem too likely. Also, without the harpoons or ice screws, it's likely that Philae will be pushed into space by gasses escaping the comet as it gets closer to the sun; so the extra sunlight is a double-edged sword.

Comment: Re:two bounces (Score 1) 223

by Thagg (#48386009) Attached to: Comet Probe Philae To Deploy Drill As Battery Life Wanes

It is fascinating that you can see stars and the comet surface at the same time; it shows how far from the sun they are. In no pictures from the moon can you see any stars.

Right now the spacecraft is about 3x as far from the sun as the moon is from the sun, so the sun is only 1/9th as bright there. I suppose the cameras might have a bit more dynamic range than the film cameras of the late 60's. The comet nucleus might also be quite dark, but the moon is very dark as well (about 10% albedo.)

Comment: two bounces (Score 5, Interesting) 223

by Thagg (#48385527) Attached to: Comet Probe Philae To Deploy Drill As Battery Life Wanes

Philae bounced twice, the first bounce was about two hours, the second one 7 minutes. If the gravity on the comet is 1/200,000th that on earth (a reasonable estimate, it varies around the comet because it's *way* not round) then the first bounce was about 1,000 feet off the surface, but the second one was only about three feet. Seven minutes to fly up and down three feet; that's almost impossible to imagine.

Comment: Re:should be banned or regulated (Score 1) 237

by Thagg (#48385103) Attached to: Will Lyft and Uber's Shared-Ride Service Hurt Public Transit?

In a city like NYC or perhaps London, I agree that the number of daily rides is a pie that will be subdivided differently. In a town like Los Angeles or even San Francisco; not so much. The number of Uber rides in LA will exceed the pre-Uber number of taxi rides soon, if it hasn't already -- it's a real game changer. Many more people are taking Uber rather than taxis, yes -- but even more people are taking Uber than used to drive.

In LA, the taxi service will suffer; but also (and maybe more so) the rental car business. It's cheaper to UberX around the city (especially if you use mass transit when you can) than renting a car; and more convenient too because you don't have to worry about parking.

Comment: Exactly the opposite! Enhances Public Transport! (Score 1) 237

by Thagg (#48385043) Attached to: Will Lyft and Uber's Shared-Ride Service Hurt Public Transit?

I use Uber in Los Angeles; as many people do.

Los Angeles has very limited subway service. It exists, it's pretty quick, but it doesn't go too many places. So, I use Uber to get to and from the subway stops closest to where I want to go; and use the train for the bulk of the transport.

Now, if I was going with a group of people instead of by myself, I'd Uber the whole way; the subway charges per person and Uber per car. But for traveling by yourself; Uber and mass transit is a great combo.

Comment: Re:A global network of high-latency torrent server (Score 5, Informative) 74

by Thagg (#48340337) Attached to: Elon Musk's Next Mission: Internet Satellites

These will not be high latency. If you have 700 satellites more-or-less evenly distributed around the globe (say from 60S to 60N latitude) and you want a minimum of 45 degree elevation to the nearest satellite, they can be lower than 400 miles altitude, or 600 miles away. Assuming that the system will bounce signals from the satellites to a distributed network of fiber connected ground stations, latency should only be 10ms more than a pure cable transmissions.

Previous satellite internet to geosynchronous satellites are nothing like this.

I agree with other commenters that this is pretty unlikely, but SpaceX and Tesla were quite unlikely to succeed as well.

Comment: Brutally sad day (Score 5, Interesting) 445

by Thagg (#48282497) Attached to: Virgin Galactic SpaceShipTwo Crashes

Burt Rutan, the designer of the Spaceship One and Two, has been a hero, perhaps the hero, of my life. A passionate, innovative aircraft designer; unbelievably aggressive in trying new things, pushing boundaries that nobody even knew existed.

His first plane design, the VariViggen was an astonishingly different design than anything out there before; designed while a student at Cal Poly and built in his garage. And it flew beautifully. I saw that plane, his later VariEze and LongEz flying in formation at the Oshkosh Fly-in in 1980.

He set up a shop at the Mojave Airport, called Rutan Aircraft Factory (RAF). In the middle of nowhere, nothing there but space to build new planes, and he built many. Each one more exotic than the last. His Boomerang, his last personal plane, is so far from the standard boring airplane designs that most people wouldn't believe it could fly; but it does fly, efficiently, safely, and every apparently crazy design idea has absolutely solid engineering and aerodynamic backing.

I took my 14-year-old daughter to see the first flight into space of Spaceship One in 2004. Burt's long-time co-worker and chief test pilot, Mike Melville, flew it that day. As it was climbing to space, it started to spin, pretty fast (about 60 rpm.) Melville said that he was scared for a second, but then decided to wait until he was "in the safety of space" to arrest the spin. A test pilot, flying an experimental winged spaceship, who has never flown to space before, in a plane spinning at Mach 3, decides in a second to wait until he was in the safety of space. And of course, it worked out; he was able to use the reaction control system to arrest the spin; took out some candy to float around the cockpit, took some photos out the windows, and enjoyed the five minutes of weightlessness. Just one of a thousand, maybe ten thousand adventures in Burt's long career.

I've wondered my whole life about how Burt responds when people die flying planes of his design. In 1983, while at Oshkosh, a VariEze crashed approaching the airport (it looks as if the linkage between the control stick and the elevator failed.) Burt, up on stage, described his trip out to the crash site. As professional as he could be, but I felt it must have been tearing him up inside. He gave the gift of flight to thousands of enthusiasts, but those great planes took the lives of some of those people. How do you reconcile that? I'm not sure I could have, or can today.

Burt got out of the homebuilt airplane business after being sued too many times by the survivors of crashes. In the last suit, the guy built the plane incredibly wrong, instead of using the 10 layers of fiberglass to attack the fins to the wing, he just glued them on. Astonishingly, it held up for years, but finally broke during a low-high-speed pass. Burt won all the lawsuits, but it was clear that he would spend years defending himself instead of doing what he loved, so he closed the shop.

Burt retired a few years ago, and lives up in Idaho instead of Mojave. Sadly, for all the innovation he created over the years, there were no commercial successes. This looked like it might be the one, but it's never going to happen.

This is not the first death in the program; sadly. While testing a previous engine about 5 years ago, the nitrous oxide detonated, killing three of his engineers. I mourned for them, and for the pilot today. My joy over my whole adult life in seeing the achievements of Rutan and his team are about evenly matched by the heartache I feel for them today. They haven't announced the name of the pilot who died today, but may he rest in peace.

Comment: not-completely-off-topic (Score 3, Interesting) 728

by Thagg (#48111233) Attached to: Why the Trolls Will Always Win

Listen the the podcast on 5x5 called "overtired". In episode 15, the incredible Christina Warren describes the shit that she gets every day, and how she deals with it. I have some hope that a younger generation of women like Ms Warren will be able to react to attacking idiots without disappearing from the 'net.

Whom computers would destroy, they must first drive mad.